SS316L Internally Welded Flanged Barred Tee with Guide Bars

What Is A Flanged Barred Tee with Guide Bars?

A Flanged Barred Tee with Guide Bars is a specialized piping component designed for branch connections in pipelines. This type of tee features guide bars on the branch side, typically made of SS316L material, to provide structural support and alignment. The guide bars are essential for ensuring proper positioning and reinforcement within the piping system.

Manufacturers of Flanged Barred Tees with Guide Bars must develop precise welding procedures to securely attach the guide bars to the tee, following industry standards such as ASME Sec. IX and NACE requirements for specific applications like sour service environments.

These tees are internally weld overlayed with materials like SS-316L, E / ER 309LMo, and E / ER316L to enhance strength and corrosion resistance. The welding of guide bars is typically carried out according to approved welding procedure specifications (WPS) and procedure qualification records (PQR) to ensure quality and reliability.

Overall, Flanged Barred Tees with Guide Bars are crucial components in pipeline systems, providing not only branch connections but also structural support, alignment, and durability for various industrial applications.

Detailed production requirements

The branch side of the barred tee shall be fitted with guide bars made of SS316L material from bar or plate. The manufacturer shall prepare a proper welding procedure for welding the guide bars with the internally cladded barred tee. The number of guide bars and their arrangement shall be in accordance with the detail provided in Appendix-4 of MR doc# BST09-OQU-0000-1200-PL-MRQ-0003-00. Guide bars shall be ground to match the smooth contour of the tee. Welding of bars shall be of full penetration and not stitch welded.

Weld overlay shall be carried out in accordance with ASME Sec. IX and additional requirements, including macro & hardness survey. Welding of guide bars shall be carried out as per approved WPS / PQR. End preparation shall be bevelled to ASME B31.4.

CS Flanged Barred Tee materials with SS Weld Overlay in sour service shall comply with the NACE requirements as per NACE MR-0175 / ISO 15156 and the Material Requisition. Flanged Barred Tee shall be internally weld overlay with SS-316L, including flange raised face. The thickness of weld overlay shall be a minimum of 3 mm undiluted and 2 layers of SS316L as a minimum. Barrier layer with E / ER 309LMo and final layer with E / ER316L with a minimum thickness of 3mm.

Flanged Barred Tee shall be manufactured in accordance with a documented MPS. Manufacturing shall not proceed until the MPS has been accepted / approved by the Company. Weld overlay deposit shall be examined with UT to identify dis-bonding as per ASME SA-578 Level C.

Dimensions and tolerances of Flanged Barred Tee shall be in accordance with MSS SP-75 / ASME B16.9 and MSS SP-44 as applicable. All material used for this project shall be new and free from any defects. Mass fraction of Sulphur shall not exceed 0.003 % for welded tee and 0.01% for seamless tee. Flanged Barred Tee shall be protected with a factory standard rust preventive temporary coating to prevent corrosion during transit.

All machined surfaces shall be suitably coated to prevent corrosion and protected against damage during transportation, storage, and installation. All flanged ends of Barred Tee shall be protected by proper covered protectors which shall be approved by the company.

Frequency of testing shall be each heat in the purchase order. The NDE requirements of Flanged Barred Tee shall be as per applicable ASTM standard / ASME Codes and additional requirements identified in MR / PO / Data Sheet.

Personnel and procedures shall be qualified in accordance with ASME Boiler and Pressure Vessel Code, Section V. Acceptance criteria shall meet the requirements of ASME Sec VIII Div-1.

Each Tee (100%) shall be ultrasonically examined, Butt-welding ends of Tee, including 1 inch beyond the weld bevel, shall be subjected to liquid penetrant or magnetic-particle examination after completion of heat treatment.

Liquid Penetrant examination shall be in accordance with ASME Section V, Article 6 with acceptance standards to ASME Section VIII Div.-I, Appendix 8. Magnetic Particle examination shall be in accordance with ASME Section V, Article 7 with acceptance standards to ASME Section VIII Div.-I, Appendix 6.

Repair of base material by welding is not permitted. Chemical composition and Hardness control shall comply as per NACE MR-0175 / ISO-15156 and shall be reported in the Certificates.

For Carbon Steel and Stainless-steel weld Overlay (316L) material maximum hardness shall not be more than 22HRC (248 HV10). Inter Granular Corrosion Test (IGC) for stainless steel materials (SS316 / SS316L) shall be in accordance with ASTM A262 Practice E.

The recorded results of all inspection and tests performed shall be submitted. Mill and shop inspection shall not relieve the Vendor from his contractual responsibility for replacing any defective material and for repairing any defective workmanship that may be discovered in the field.

Pecial Notes:

i) Weld Overlay :
a. Weld overlay shall be carried out in accordance with ASME Sec. IX and additional requirements as follows including macro & hardness survey.
b. Barrier layer shall be used with E/ER309LMo type filler and subsequent layer shall be with E/ER316L filler metal
c. Welding processes shall be limited to GTAW/ SMAW/GMAW/SAW
d. WPS/PQR shall be qualified with IGC test in accordane with ASTM A262 Practice. E
e. Minimim qualified thickness from fusion line shall be clearly specified in WPS/PQR and from that 3mm undiluted chemistry shall be confirmed.
f. Ferrite test on final layer and Liquid penetration test on each layer shall be carried out.
e. Sample specimen for hardness test shall be as per NACE MR0175/ISO 15156.
ii) NDE on Production weld overlay:
a. 100% LPI shall be carried out on each layer
b. Ferrite and PMI verification shall be carried out on final layer
c. Weld overlay thickness verification by magnetic method or equivalent
d. 100% UT disbondment test as per ASTM A578, Level C shall be carried out to confirm 100% fusion with CS base material.
iii) NDE of Butt welds – 100% Visual, 100% RT, 100% MT or PT, Hardness test
Flanged Barred Tee shall be inspected, tested, marked and supplied in accordance with requirements in requisition & specification.